GLMixer Code

preliminary implementation of hardware codec decoding under OSX

Improved listing of volumes in custom file dialogs

BugFix: no change to source when cancel custom mask file.

BugFix: display error message on error creating basket source.

Added preference option to disable the hardware codec. Improved file open
dialog to offer option to enable/disable hardware codec. Default to
disabled hardware codec.

BugFix (Ticket #75 GLMixer Control panel window stretches off of
screen.): information text in status bar eluded to fit in window.

Updated File Dialog to offer option to use GPU decoding.

Improved detection of capabilities and user selection for the use of GPU
accelerated decoding: currently supporting nvidia CUVID (if compiled in
ffmpeg lib).

Do not try to use hardware codec decoding by default, and only offer the
option in the property manager.

Improved support for recording. In order of preference (and performance); 1) glReadPixels with PBO, 2) glGetTextureSubImage is extension exists, 3) glGetTexImage (universal opengl).